Ruth Porter Crawford did not live to hear the first public performance of her sonata for violin and piano, though she composed it in 1926 and survived until 1953. The premiere finally happened last night in the Library of Congress, where the unpublished manuscript of the work is kept, and it sounded more than half a century overdue. Hearing it, one wonders what music Ruth Crawford could have composed in her maturity if she had not married musicologist Charles Seeger and spent her later years at their home in Silver Spring, transcribing thousands of folk songs.

The sonata is a masterpiece, almost at the level of her better-known String Quartet, which was composed five years later. It stood out, even amid music of Wallingford Riegger, Dane Rudhyar, Carlos Cha'vez, Aaron Copland, Henry Cowell and others, in a brilliant program that was one of the finest I have ever heard at the library. Using a highly chromatic language that verged on atonalism, the sonata had vitality, imagination, deep dramatic power and an eloquence equal to the most impassioned human voice. There was a bouncy scherzo that lived up precisely to its tempo marking: "buoyant," and a slow movement that was, as instructed, "mystic, intense." It should be a standard work in modern violin literature, and probably will be if violinist Ida Kavafian continues to play it as she did last night.

Kavafian (deservedly one of the best-known young chamber musicians in the country) had a magnificent partner in Vivian Fine, who was a student of Ruth Crawford and donated the manuscript of the sonata to the library. Fine, better known as a composer but also a superb pianist, played in two other striking works on the program: the Cha'vez sonatina for violin and piano (with Kavafian) and a powerful song for soprano and piano, "The Corpse," by Leon Ornstein (with soprano Judith Bettina).

Other highlights of this remarkable program included Riegger's splendidly lyric Suite for Flute Alone, played by Sue Ann Kahn; piano music of Dane Rudhyar, Adolph Weiss and Colin McPhee, powerfully interpreted by pianist Richard Becker; Copland's song "As It Fell Upon a Day," and Cowell's Mosaic Quartet.

The Cowell work, played by violinists Rolf Schulte and Joel Lester, violist Jacob Glick and cellist Christopher Finckle, was a fascinating study in string textures, often setting one instrument (a rhapsodic violin or gruff cello) in contrast against the others.

Of special interest was the Copland song, which has been described as his first mature composition (it dates from 1923) but would hardly be recognized as a Copland work by a casual listener today. It is a fascinating blend of ancient and modern styles, with elaborate vocalises on the syllable "A" at the beginning and end and occasional cadences that echo the 17th-century pastoral flavor of the text by one Richard Barnefield. Among other charms, it includes some bird imitations for flute and clarinet, which were beautifully played by Kahn and Virgil Blackwell to match Bettina's impressive singing.

Most of the music originally was published by New Music magazine, a quarterly founded by Cowell in 1927, and all of the composers on the program were associated with the magazine, as were such others as Virgil Thomson, Charles Ives, Carl Ruggles and Edgar Vare se. If last night's program was a fair sample, an annual Library of Congress concert focusing on the New Music composers could become one of its most distinguished traditions.